SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de2cd186a3e8911438a6c284ea9b3e412de5aa9e159759c23d4c082723a4e8e1' 
  AND token = 'v0quxuCNFduLetm1qW8IPc0HKLBzmh+Mj47ZX7w0hdQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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