SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19560fb8aa11bf405753aaf251445079eb7130e5b7b057e805a6448e2fe68d97' 
  AND token = 'zKB+TOVu3gKIIyUXK5BkilKUSZRJD6nphf6U2j4JenY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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