SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c24d23439ed2355e637a7bcffa76a5773599c93829ed65556e898a87229a1888' 
  AND token = 'Svs7xphEfY9fIxxBn2oO0KwYa8YqvOsr29qMLbBS4GY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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