SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0797a31cd652836a2067608f8d999ed4f3d0873c81826df0148b021d5b265a81' 
  AND token = 'c9zoJ3o5dJ4v8Y2Yv2cj/o76k03eo3hhL4GcxZgdhEI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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