SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5fce55494ecdfea1befb5f6ddb7e2ef22a160203448c067bedf184b20684ffbc' 
  AND token = 'mQ8NxQ0ewSVL+xvXD4jDCsSg6xIFNF70ENx57Dt9TPQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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