SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f182976acdf195b9e93da73fd286796cf57a4328bf278be07edffa49249541f' 
  AND token = '1hmhXsjS/cPqtKVs04AVBPdeWssZgnaR3Tvw4Fz/c1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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