SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f19bac423e746604769a674d31055413086ae9968330a900fe549a3c2d15e83' 
  AND token = '4AX70vrz0BNYORUIeyGK+mtE3ZKtG4z5nVFS5JitytI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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