SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0a74d711759c7966553df1c2f575f4100392623cbe7f051d62455ef37a13861' 
  AND token = 'pQlRDXhinfPnfnoL7FAXC6M6XcedlNdHBl9lUWhRNOE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}