SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '140652e414a3a7d27ac2dec344b6d92a53965128e6fc99ab0ebcdd3208345375' 
  AND token = 'ADN1h/T8dGdgVdfmuUU9vgTbJsXgr6jw6GQRT3zW+KY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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