SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0bcbb32fbc562aff130e13edf15a979635e23315add7f654a4cdbcdeeaec7dc' 
  AND token = 'CpQ2LUcjAwOmIhrzZoaBhe5qTM7E4mglfztR7wyBc98=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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