SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc84a1dd7c9093eebb42afc0857467404553d0e37805a4755e517bd22316b3b5' 
  AND token = 'UVmzDqsCBXjSnCrt1HL6mDgN0+rBGqY1971ZJQR0GYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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