SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2f4ed4ef980eda5b4a32bddf093794deb52f2c2045840559067ce05056bf62e' 
  AND token = 'TIbH/cz3nmBqdh0Jc5Q09MXGYO5HI7rOvVvrWsJsI/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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