SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e7c44c0fe997c7ccf73d4a3c7582ef2f3d65598c01cdb968612bd405b3823a9' 
  AND token = '6NDYWMhz0fCEbVqPHrn7FefynrjCR8QXFZZ6vbR026g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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