SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '064d722de97e7e916f80666f684311b7251e6bfd200a35259dee45717dae5779' 
  AND token = 'hs/C0pqVMvPp2PPKnRi836/Teld0v7nayURyv4BXbzY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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