SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2643ae63dde4d066a9da372bc07d30f1cfec459cd2415ddac3eaf30a7f852a1' 
  AND token = '4xL3OcmwrC5yowunPKEecjktBUj9rriQQzOSKwUuZu4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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