SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '21a45df6cd22bab8d343f4ac5e441bb4b225a5ad56f710ac422cae244fc41ba0' 
  AND token = 'IAzQT8aZLP3aANtuBss4k3lXXCGblgsETkSd9EQ2fAM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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