SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b2d61c2eb13b7a40a8d6c396e9c7d12dc9d5215a0b58709254a440130aac501' 
  AND token = 'ZDIKL2qajhdOPH643gVExGYyfVjlyLsawu/Tq6LuvPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}