SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88f9729f1592a5dd381d5d290ae174c43161721c65ab096addf9f6ae82d37cc6' 
  AND token = 'REc1h7uAsZQkCh2R+I4v3RxtypciRt8UQQoC7l2z3WY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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