SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed39c1780788d4a0a3eb009ba4240bd116fb9cdadbadad6e24271ac90568ae24' 
  AND token = 'esqjKTZksjATGu2ul48zN2AcQ5Nh/pVGPccfurV9y1g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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