SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f67b83d8906d3da771b4b981cedc9bd33e2a8fcf62bd76df008080b6a7a04bf4' 
  AND token = 'n1fjJnEMCOJUBswNKrNNxVTLPDnECDqzXHMzVWTreF4=' 
  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"
    }
  }
}