SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22936240635e9c4cdf47de2ff2492360c571c45350cd610d52cff71e48018acc' 
  AND token = 'DfJIObHOwD0C9r1UgQrNp6a2oKT2E7/xxVJgtcLpi0c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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