SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9455744fb46748eed8bc19757fa27d1ad0839806042db6c6d91de2155a7cfd17' 
  AND token = 'doWdeYR1AFufiRivOFej7wgCT5qgYgtK8UhXj7o6qVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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