SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '444faa88d594c1ebcb1c1d90d5db555b0887d4421a23a826c18f9884c7008152' 
  AND token = 'PO30mz/rPTKQFiDzjmYgrpDOooaMKzicv1441GznSek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}