SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c1d06fde5891a07c2e7aafe6cdb0db33aaf45f5886f171c5d2dd1093347ffbc' 
  AND token = 'd1JCJyqxjfCNMUxvVO5pGN/tFuv/fsXhukBx2lSIe3k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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