SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed21ae6f845611eeec47458dd0510874134ea18c4868ad833f9433dfc3ad8517' 
  AND token = 'jxIz4zjqlYlBU5ehirTZHEEwxUEy+mPEM88CrN4kmDQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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