SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '165793707d2aa85235fad09e089dbfc61631fbd6d6a7cf81a5be3dd28857faf7' 
  AND token = 'K7E+uLsCSvKC+/EOkLDolZWJUovOMrjYAtGl46Nlmaw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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