SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72ba72d37c1c63192b811fb8d249e3565c86df8db91dc2c4e17bb8f260af37ab' 
  AND token = 'ktEiefKE4ldgQ8R7y2obCNbdXRBBOBl7GzJBjZER10c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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