SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7031f8b2a268ff3720978eb65c2661a770b73dadd2e4f46aaf45fe023746b2bb' 
  AND token = '0xf48zhbzcmmJwfxGYSAIDGhSzLWNJQxJPFrwCvL+Hw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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