SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b772565a97a8d3528903d1c18a28a5e195d4bc05dbd7b23bb37618d58f319095' 
  AND token = 'UPdEJQdhJ2wDSyBv9N19PT8/J8oFVHLorGekN1pTSRA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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