SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e18ec8889fdf64350d429410aec51cff9c45bf08dc9f8adb93cd76d91dc2dfd' 
  AND token = 'EaIeunwm2MfFAMxFjJ/62dRuFNlt4rWghC2MwW7qo48=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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