SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a75269d9d88f25782d1440404107d0c43b7836d38fe5fa18a4fd4d19aec1b6a' 
  AND token = 'BtldFfye5U4JegM7yazghHILSB1XhJWdmFIxtcQbB4I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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